Amazing book!!!!!! Truly. This book properly introduced me to Lacan. I read this book 2 years ago, and have been studying Lacan ever since. This book was crucial for me. This book also gave me a greater understanding of Zizek... one cannot read Zizek without being familiar with Lacan.
I was looking for an introduction to Lacan that would be both concise and yet in-depth enough to give me a sense of the breadth and significance of Lacan's thought. This book succeeds admirably in both respects. The author clearly has a thorough grasp of Lacan's main ideas, but he has boiled them down into six compact and well-written chapters. To be sure, it is hard to truly grasp Lacan (or any path-breaking thinker) on the first pass, and it helps if you know a little bit about Freud. Nonetheless, Horner meets his audience more than half way: for example, he does not assume that readers know Freud's theory of the Oedipus complex, nor does he assume any familiarity with Saussure, Levi-Strauss, Jakobson, or other figures crucial to Lacan's intellectual milieu. At the same time, however, Horner provides more than just a summary of Lacan's ideas--he also shows how they have been used by scholars to study film, analyze racism, and so forth. Those seeking more information are referred to the excellent "Further Reading" section, which doesn't just list books but discusses their merits and shortcomings. All in all, an excellent introduction to the works of Lacan.
This is a very clearly written book. Homer is able to give a comprehensive explanation of Lacan's basic concepts in the following areas; imaginary and the symbolic, the Oedipus complex and the meaning of the phallus, the subject and the unconscious, the real and sexual difference. It's not a long book and it doesn't really have much to say on the subject of psychopathology being instead more focused on demonstrating the relevance of Lacan to cultural studies. This book however complements Lionel Bailly's excellent introductory text 'Lacan' which is a bit more complicated in it's focus on the relationship between language, the unconscious and psychopathology.
I have been struggling with Lacan for some time and have read several introductions. Sean Homer's book is one of the best; therefore I would like to recommend it. Homer concentrates on the most important concepts in Lacan's philosophy and gives at the end of each chapter a short summery. May be this takes away much of the complexity of Lacan's thought, but knowing what his writing is all about might be still very helpful before entering in the labyrinth of the French philosopher's thought.